Robert Mueller is reportedly zeroing in on Jared Kushner over his role in firing James Comey

Kevin Lamarque/Reuters

Donald Trump and Jared Kushner.

• White House senior adviser Jared Kushner turned over documents to special counsel Robert Mueller's investigators.
• Investigators are asking questions about Kushner's role in firing James Comey as FBI director.
• Sources close to the White House say they don't believe he's a target of the investigation.

White House senior adviser Jared Kushner turned over documents to special counsel Robert Mueller as investigators have expressed interest his role in the May firing of James Comey as FBI director, CNN reported Thursday.

CNN reported that Kushner, President Donald Trump's son-in-law, turned over the documents to Mueller "in recent weeks." Mueller's Russia probe recently led to the indictments of former Trump campaign chairman Paul Manafort and his past business associate Rick Gates, as well as a guilty plea from George Papadopoulos, a foreign policy adviser on the campaign, for making false statements to the FBI.

Mueller's investigators have been asking about Kushner's role in Comey's firing in witness interviews, sources told CNN. Meanwhile, sources close to the White House told CNN that, "based on their knowledge," Kushner is not a target of Mueller's investigation. Kushner voluntarily turned over the documents, which were similar to the ones he provided congressional investigators earlier this year, CNN reported.

The questions of both how much Kushner influenced Trump's decision to fire Comey and why Kushner would want the FBI director fired are disputed by those close to Trump, CNN wrote.

Comey's May firing ultimately led Deputy Attorney General Rod Rosenstein to appoint Mueller, who is overseeing a wide-ranging investigation into Russia's meddling in the 2016 US election. Comey had previously been overseeing a similar investigation at the FBI, leading to questions about whether Trump obstructed justice by firing him.

CNN's report came one day after Vanity Fair reported that Trump was becoming frustrated with Kushner.

Citing a source briefed on a Tuesday call between Trump and former White House chief strategist Steve Bannon, Vanity Fair's Gabriel Sherman reported that Trump blamed Kushner "for his role in decisions, specifically the firings" of Michael Flynn as White House national security adviser and Comey as FBI director.

Trump also told his longtime adviser Roger Stone that he agreed with Stone's assessment that Kushner was providing him bad political advice, someone familiar with the conversation told Vanity Fair.

"Jared is the worst political adviser in the White House in modern history," Sam Nunberg, a former Trump campaign operative, told Vanity Fair. "I'm only saying publicly what everyone says behind the scenes at Fox News, in conservative media, and the Senate and Congress."